No, soccer will not "explode" in the US. It will however continue to get extremely popular. As many have mentioned, the MLS has learned from past league's mistakes (salary cap, the MLS actually owns every team, soccer specific stadiums) and is slowly expanding into markets (Atlanta, Miami) that have large ethnic populations. Teams such as Seattle, Portland, Salt Lake, Kansas City, Philadelphia, etc have large fan support groups. The American Outlaws grew out of this to support the USMNT and they now have over 130+ chapters across the US. You can now watch just about every game from every major league (Premier league, la liga, etc) and millennials love it. One of the biggest hurtles soccer in the US faces is nuturing home grown talent. Klingsmann has made it his mission to put into place the European system where you start nuturing kids young and have the MLS teams have academies to develop those kids. Once that starts to bear fruit (10-20 years) and the MLS starts to pay a competitive wage compared to other sports, the US could be quite competitive.